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Backgrounds Folate Hydrolase‐1 (FOLH1; PSMA) is a type II transmembrane protein, luminally expressed by solid tumour neo‐vasculature. Monoclonal antibody (mAb), J591, is a vehicle for mAb‐based brachytherapy in FOLH1+ cancers. Brachytherapy is a form of radiotherapy that involves placing a radioactive material a short distance from the target tissue (e.g., on the skin or internally); brachytherapy is commonly accomplished with the use of catheters, needles, metal seeds and antibody or small peptide conjugates. Herein, FOLH1 expression in primary (p) and metastatic (m) Merkel cell carcinoma (MCC) is characterized to determine its targeting potential for J591‐brachytherapy. Materials & Methods Paraffin sections from pMCC and mMCC were evaluated by immunohistochemistry for FOLH1. Monte Carlo simulation was performed using the physical properties of conjugated radioisotope lutetium‐177. Kaplan–Meier survival curves were calculated based on patient outcome data and FOLH1 expression. Results Eighty‐one MCC tumours were evaluated. 67% (54/81) of all cases, 77% (24/31) pMCC and 60% (30/50) mMCC tumours were FOLH1+. Monte Carlo simulation showed highly localized ionizing tracks of electrons emitted from the targeted neo‐vessel. 42% (34/81) of patients with FOLH1+/− MCC had available survival data for analysis. No significant differences in our limited data set were detected based on FOLH1 status (p = 0.4718; p = 0.6470), staining intensity score (p = 0.6966; p = 0.9841) or by grouping staining intensity scores (− and + vs. ++, +++, +++) (p = 0.8022; p = 0.8496) for MCC‐specific survival or recurrence free survival, respectively. Conclusions We report the first evidence of prevalent FOLH1 expression within MCC‐associated neo‐vessels, in 60‐77% of patients in a large MCC cohort. Given this data, and the need for alternatives to immune therapies it is appropriate to explore the safety and efficacy of FOLH1‐targeted brachytherapy for MCC. What's already known about this topic? We report the first evidence of prevalent folate hydrolase‐1 (FOLH1; also known as prostate‐specific membrane antigen) expression within MCC‐associated neovessels. What does this study add? Herein, FOLH1 expression in Merkel cell carcinoma neovasculature is validated, and the therapeutic mechanism of specific, systemic targeting of disseminated disease with antibody‐based brachytherapy, is defined.

Treatment of refractory palmar-plantar vitiligo is particularly challenging because the skin in these regions has a limited supply of follicle-derived melanocytic stem cells. Autologous hair transplantation monotherapy is effective in some forms of vitiligo through the provision of melanocytic stem cells. CO2 laser followed by exposure to light (i.e., sunlight or narrow-band ultraviolet-B [nbUVB]) has independently shown to be an effective treatment strategy. Recently, it was found that the combination of hair transplantation and CO2 laser followed by nbUVB exposure had superior efficacy to either modality as monotherapy. Similar to CO2 laser, microneedling produces skin cell proliferation and releases pro-pigmentary cytokines. Given the important role of the cytokines in vitiliginous skin, microneedling may also be an effective therapeutic modality for refractory vitiligo. Herein, we conducted a pilot study to evaluate the efficacy of hair transplantation and CO2 laser or microneedling followed by nbUVB. Microneedling and fractional CO2 laser in combination with hair transplantation and nbUVB both demonstrated utility in the induction of repigmentation in refractory palmar-plantar vitiligo; however, a larger trial would be needed to determine a difference in treatment efficacy. Nonetheless, microneedling is cost-effective and requires minimal training; therefore, microneedling can be easily incorporated into standard dermatological practice.

Psychological morbidity, sexuality, and health/system information have been identified as the highest areas of support needs in patients undergoing management of their prostate cancer (PCa). Management of a patient's sexual function prior to, during and after PCa radiotherapy requires multidisciplinary coordination of care between radiation oncologists, urologists, dermatologists, pharmacists, and psychiatrists. The finale of this three-part review provides a framework for clinicians to better understand the role of mental healthcare providers in the management of sexual toxicities associated with prostatic radiotherapy. The authors recommend that patients be referred for psychological evaluation and possibly to individual, couples or group general or cognitive behavioral sex therapy at the time of their PCa diagnosis, for a more specialized focus on management of sexual toxicities and sexual recovery. The importance and implications of the masculine self-esteem, sexual orientation, gender identification, cultural expectations, relationship status and patient education are reviewed. Well-informed patients tend to have a better quality of life outcomes compared to patients that take on a passive role in their cancer management.

Prostate cancer is the most common malignancy and the second leading cause of cancer-related death in men. Radiotherapy is a curative option that is administered via external beam radiation, brachytherapy, or in combination. Erectile, ejaculatory and orgasm dysfunction(s) is/are known potential and common toxicities associated with prostate radiotherapy. Our multidisciplinary team of physicians and/or scientists have written a three (3) part comprehensive review of the pathogenesis and management radiation-induced sexual dysfunction. Part I reviews pertinent anatomy associated with normal sexual function and then considers the pathogenesis of prostate radiation-induced sexual toxicities. Next, our team considers the associated radiobiological (including the effects of time, dose and fractionation) and physical (treatment planning and defining a novel Organ at Risk (OAR)) components that should be minded in the context of safe radiation treatment planning. The authors identify an OAR (i.e., the prostatic plexus) and provide suggestions on how to minimize injury to said OAR during the radiation treatment planning process.

Prostate cancer is the most common malignancy in men and the second leading cause of cancer-related death in men. Radiotherapy is a curative option that is administered via external beam radiation, brachytherapy, or in combination. Sexual dysfunction is a common toxicity following radiotherapy, similar to men undergoing radical prostatectomy, but the etiology is different. The pathophysiology of radiation-induced sexual dysfunction is multi-factorial, and the toxicity is a major cause of impaired quality of life among long-term prostate cancer survivors. Management of a patient's sexual function during and after radiotherapy requires multidisciplinary coordination of care between radiation oncology, urology, psychiatry, pharmacy, and dermatology. This review provides a framework for clinicians to better understand prostatic radiotherapy-induced sexual dysfunction diagnosis, evaluation, and a patient-centered approach to toxicity preventive strategies and management.

Purpose Infection by Human Herpes Viruses (HHV) types 1–3, are prevalent throughout the world. It is known that radiotherapy can reactivate HHVs, but it is unclear how and to what extent reactivations can interact with or affect radiotherapeutic efficacy, patient outcomes and mortality risk. Herein, we aim to summarize what is known about Herpes Simplex Virus (HSV)-1,2 and Varicella Zoster Virus (VZV) pathophysiology as it relates to tumor biology, radiotherapy, chemo-radiotherapy, diagnosis and management so as to optimize cancer treatment in the setting of active HHV infection. Our secondary aim is to emphasize the need for further research to elucidate the potential adverse effects of active HHV infection in irradiated tumor tissue and to design optimal management strategies to incorporate into cancer management guidelines. Materials and methods The literature regarding herpetic infection, herpetic reactivation, and recurrence occurring during radiotherapy and that regarding treatment guidelines for herpetic infections are reviewed. We aim to provide the oncologist with a reference for the infectious dangers of herpetic reactivation in patients under their care and well established methods for prevention, diagnosis, and treatment of such infections. Pain management is also considered. Conclusions In the radiotherapeutic setting, serologic assays for HSV-1 and HSV-2 are feasible and can alert the clinician to patients at risk for viral reactivation. RT-PCR is specific in identifying the exact viral culprit and is the preferred diagnostic method to measure interventional efficacy. It can also differentiate between herpetic infection and radionecrosis. The MicroTrak® HSV1/HSV2/VZV staining kit has high sensitivity and specificity in acute lesions, is also the most rapid means to confirm diagnosis. Herpetic reactivation and recurrences during radiotherapy can cause interruptions, cessations, or prolongations of the radiotherapeutic course, thus decreasing the biologically effective dose, to sub-therapeutic levels. Active HHV infection within the treatment volume results in increased tumor radio-resistance and potentially sub-therapeutic care if left untreated. Visceral reactivations may result in fatality and therefore, a high index of suspicion is important to identify these active infections. The fact that such infections may be mistaken for acute and/or late radiation effects, leading to less than optimal treatment decisions, makes knowledge of this problem even more relevant. To minimize the risk of these sequelae, prompt anti-viral therapy is recommended, lasting the course of radiotherapy.

Cutaneous injury can ignite excessive fibroproliferative growth that results in keloid formation. Keloids are associated with significant morbidity related to disfigurement and/or symptoms (e.g., pain and pruritus). First-line treatment of formed keloids involves topical or intralesional steroids. Recurrent or resistant keloids are managed by surgical excision or cryotherapy, followed by steroidal application or adjuvant irradiation. Although adjuvant irradiation appears to be most efficacious, alternative therapeutic options are needed for patients without access to radiation centers. Botulinum Toxin A (BTA) appears to have similar inhibitory effects to irradiation on the cell cycle via downregulation of pathogenic cytokines. Herein, we conducted a study to compare the efficacy of intralesional triamcinolone used alone, or in combination with BTA, in the treatment of formed keloid scars. Twenty patients with a cumulative of 40 keloids completed the study. There was no significant difference between treatment arms with respect to height vascularization, pliability, and pigmentation scores. The addition of BTA resulted in significant symptomatic improvement of pain and pruritus as compared to intralesional triamcinolone alone (p < 0.001). Irradiation is only effective when administered in the adjuvant setting where inhibitory effects on cell cycle and migration are optimized. Future studies with intralesional triamcinolone and BTA should be performed adjuvantly.

After cutaneous injury, cytokine mediators recruit an inflammatory infiltrate that stimulates migration of keratinocytes and fibroblasts; subsequent proliferation of fibroblasts and keratinocytes begins 4 to 5 days later [1]. The formation of a keloid is dependent upon fibroblast migration, proliferation and type III collagen production [1]. First{\hyphen}line treatment of keloids involves topical or intralesional steroids. Recurrent or resistant keloids are managed by surgical excision or cryotherapy, followed by steroidal application, that presumably limits inflammation and cellular migration. Adjuvant irradiation to surgical excision is an alternative but underutilized modality that has demonstrated superior patient satisfaction and local control compared to post{\hyphen}cryotherapy or resection intralesional steroids, respectively [2, 3]. This article is protected by copyright. All rights reserved.

To use the Surveillance, Epidemiology, and End Results (SEER) Database to analyze the impact of postoperative radiation after limb sparing surgery for high-grade extremity soft tissue sarcomas (STS).We identified patients, aged 20 to 79, who were diagnosed between 1988 and 2006 with high-grade STS of the extremities and underwent radical limb sparing surgery with or without postoperative external beam radiation. Kaplan-Meier and Cox regression analyses were performed to evaluate the effect of postoperative external beam radiation therapy on overall survival (OS) and disease-specific survival (DSS).A total of 983 patients met the selection criteria: 788 (80.2%) received postoperative radiation and 195 (19.8%) underwent surgery alone. For the whole cohort, there were no differences between the groups in OS (P=0.06) or DSS (P=0.20). On subgroup analysis, for tumors ≤5 cm there remained no significant differences in OS (P=0.8) or DSS (P=0.93). However, for tumors5 cm the 3-year OS improved with the addition of postoperative radiation from 55.6% to 73.4% (P0.001). Similarly, the 3-year DSS improved from 68.1% to 80.6% (P=0.005).Because of the retrospective nature of this study and inherent limitations of the SEER database, a large prospective study is needed to further elucidate the relationship between postoperative radiation and survival. However, these data do support the use of adjuvant radiation for patients with high-grade extremity STS measuring5 cm.

Purpose/Objective(s) Prostate-specific membrane antigen (PSMA), also known as folate hydrolase 1 (FOLH1), is a highly specific biomarker and therapeutic target for prostate cancer (PC). J591, a monoclonal antibody specific to PSMA, is the primary method used to detect PSMA expression. It is currently under investigation as a vehicle to deliver targeted therapies to PC cells. Androgen deprivation therapy (ADT) upregulates PSMA. Preclinical models of androgen resistant (AR) xenografts demonstrate PSMA upregulation by ADT increases the therapeutic index of J591-drug conjugates, suggestive of enhanced drug uptake. We sought to evaluate the effect of external beam radiation (EBRT) on PSMA expression in PC cells ± ADT. Methods Androgen sensitive LNCaP and AR CWR22Rv1 PC cell lines were cultured in standard and charcoal-stripped media for two weeks. Both cell lines were grown in both media conditions, and received either no EBRT, EBRT in 2 Gray (Gy) daily fractions to a maximum of 10 Gy, or 7.5 Gy in 1 fraction. Cell surface PSMA expression was measured by flow cytometry as mean fluorescence intensity 24 hours after each 2 Gy fraction, or on days 1, 3, 5, 7, and 9 after 7.5 Gy. Results LNCaP in standard media upregulated PSMA by 2.97-fold (SEM ± 0.72) with fractionated EBRT to a cumulative dose of 4 Gy, peaking on days 2 and 3 after 4 Gy and 6 Gy cumulative doses, respectively. CWR22Rv1 in standard medium, upregulated PSMA expression by 3.21-fold (SEM ± 0.44) after a cumulative dose of 8 Gy, peaking on day 4. Under ADT (charcoal-stripped media), EBRT did not further increase LNCaP cell PSMA expression (maximal fold-change of 1.01 (SEM ± 0.02)) relative to ADT alone. Compared to CWR22Rv1 with ADT alone, ADT plus EBRT upregulated PSMA by 3.73-fold (SEM ± 0.44) after a cumulative fractionated dose of 8 Gy, and peaking on days 4 and 5. However, 7.5 Gy in one fraction did not significantly increase PSMA expression of LNCaP or CWR22Rv1 in standard media. LNCaP showed a maximal fold-change of 1.14 (SEM ± 0.29) on day 9. CWR22Rv1 showed a maximal fold-change of 1.27 (SEM ± 0.02) on day 1. Conclusions We show PSMA expression is independently enhanced by ADT and by low-dose fractionated EBRT, but not with single-fraction ablative EBRT. These observations warrant additional studies using in vitro and in vivo PC models to validate our findings. PSMA upregulation may aid in optimizing J591 targeting for treatment of local and disseminated or micrometastatic disease. Validation of PSMA upregulation by ADT and EBRT supports use of J591-drug conjugates as an adjunct treatment to these standard therapies for PC. Furthermore, if fractionated EBRT upregulates PSMA, then targeted brachytherapy using appropriately selected J591-radionucleotide conjugates may increase its own therapeutic index in a time-dependent manner as a result of regional low-dose rate beta or alpha emission. Citation Format: Marigdalia K. Ramirez-Fort, Sean S. Mahase, M. Junaid Niaz, He Liu, Vincent Navarro, Goran Rac, Harry S. Clarke, Scott T. Tagawa, Joseph M. Jenrette, Neil H. Bander, Christopher S. Lange. External beam radiation therapy and androgen deprivation therapy increase PSMA expression in prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1774.

Folate hydrolase-1 (FOLH1) is a type II transmembrane protein. Oncologically, FOLH1 is upregulated throughout prostate cancer cells; it is also luminally expressed by the neovasculature of most solid tumors but not by normal vessels. J591, a monoclonal antibody (AB), is specific to, and is effectively endocytosed after extracellular binding to, FOLH1. J591 is presently being developed in clinical trials as a vehicle for AB-based brachytherapy in FOLH1+ cancers. Merkel cell carcinoma (MCC) is a rare, neuroendocrine tumor; metastatic (m) MCC is associated with poor survival. We characterized FOLH1 expression in MCC to determine its target potential for J591-brachytherapy. Paraffin sections from primary (p) and mMCC were deparaffinized and rehydrated. Samples were stained with 3E6 (DAKO), a mouse IgG1 monoclonal anti-human FOLH1. Mouse IgG1 (10 ug/mL in 1% bovine serum albumin) was used as an isotype-matched negative control. Anti-CD31 (IgG1) was used as a positive control. Kaplan-Meier survival curves were calculated based on patient outcome data and FOLH1 expression. 81 MCC tumors were evaluated. 67% (54/81) of all cases with 77% (24/31) of pMCC and 60% (30/50) of mMCC tumors demonstrated FOLH1+ neovessels. No cellular staining of tumor cells was identified. 34 patients with FOLH1 +/- MCC were demographically homogeneous in terms of sex, age, immunosuppression status, prior therapies, stage at diagnosis, and local or distant recurrences. No significant differences were detected based on FOLH1 status, in regards to MCC specific survival (P=0.905), or overall survival (P=0.687), as measured from time of diagnosis. FOLH1 is expressed in the majority of pMCC and mMCC cases and is nonprognostic. Our findings support further investigation of targeted therapy with J591-brachytherapy for the management of MCC. Citation Format: Barbara Meier, Marigdalia K. Ramirez-Fort, Kristina Lachance, Candice D. Church, Sean S. Mahase, Joseph M. Jenrette, Christopher S. Lange, Lars E. French, Paul Nghiem, Neil H. Bander. Folate hydrolase-1 is a novel target for J591-brachytherapy in Merkel cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2518.

Purpose: The purpose of this article was to determine the suitability of the prostate and seminal vesicle volumes as factors to consider patients for treatment with image-guided 3D-conformal radiation therapy (3D-CRT) or intensity-modulated radiation therapy(IMRT), using common dosimetry parameters as comparison tools. Methods: Dosimetry of 3D and IMRT plans for 48 patients was compared. Volumes of prostate, SV, rectum, and bladder, and prescriptions were the same for both plans. For both 3D and IMRT plans, expansion margins to prostate + SV (CTV) and prostate were 0.5 cm posterior and superior and 1 cm in other dimensions to create PTV and CDPTV, respectively. Six-field 3D plans were prepared retrospectively. For 3D plans, an additional 0.5 cm margin was added to PTV and CDPTV. Prescription for both 3D and IMRT plans was the same: 45 Gy to CTV followed by a 36 Gy boost to prostate. Dosimetry parameters common to 3D and IMRT plans were used for comparison: Mean doses to prostate, CDPTV, SV, rectum, bladder, and femurs; percent volume of rectum and bladder receiving 30 ( V 30 ) , 50 ( V 50 ) , and 70 Gy ( V 70 ) , dose to 30% of rectum and bladder, minimum and maximum point dose to CDPTV, and prescription dose covering 95% of CDPTV ( D 95 ) . Results: When the data for all patients were combined, mean dose to prostate and CDPTV was higher with 3D than IMRT plans ( P 0.01 ) . Mean D 95 to CDPTV was the same for 3D and IMRT plans ( P > 0.2 ) . On average, among all cases, the minimum point dose was less for 3D-CRT plans and the maximum point dose was greater for 3D-CRT than for IMRT ( P 0.01 ) . Mean dose to 30% rectum with 3D and IMRT plans was comparable ( P > 0.1 ) . V 30 was less ( P 0.01 ) , V 50 was the same ( P > 0.2 ) , and V 70 was more ( P 0.01 ) for rectum with 3D than IMRT plans. Mean dose to bladder was less with 3D than IMRT plans ( P 0.01 ) . V 30 for bladder with 3D plans was less than that of IMRT plans ( P 0.01 ) . V 50 and V 70 for 3D plans were the same for 3D and IMRT plans ( P > 0.2 ) . Mean dose to femurs was more with 3D than IMRT plans ( P 0.01 ) . For a given patient, mean dose and dose to 30% rectum and bladder were less with 3D than IMRT plans for prostate or prostate + SV volumes 65 (38/48) and 85 cm 3 (39/48), respectively ( P 0.01 ) . The larger the dose to rectum or bladder with 3D plans, the larger also was the dose to these structures with IMRT ( P 0.001 ) . For both 3D and IMRT plans, dose to rectum and bladder increased with the increase in the volumes of prostate and seminal vesicles ( P 0.02 to 0.001). Conclusions: Volumes of prostate and seminal vesicles provide a reproducible and consistent basis for considering patients for treatment with image-guided 3D or IMRT plans. Patients with prostate and prostate + SV volumes 65 and 85 cm 3 , respectively, would be suitable for 3D-CRT. Patients with prostate and prostate + SV volumes > 65 and 85 cm 3 , respectively, might get benefit from IMRT.

Background Patients undergoing sublobar resection for early-stage non-small cell lung cancer may receive adjuvant radiation therapy in an effort to improve outcomes despite limited data regarding its efficacy. Methods Using the Surveillance, Epidemiology, and End-Results (SEER) registry we identified patients diagnosed with stage I non-small cell lung cancer between 1988 and 2003 who were definitively treated with sublobar surgical resection with or without adjuvant external beam radiation therapy. Kaplan-Meier, Cox regression, and propensity-score-matched survival analyses were performed to evaluate the effect of adjuvant external beam radiation therapy on survival. Results A total of 5,908 eligible cases were identified: 493 received external beam radiation therapy and 5,415 received no additional local-regional treatment. The use of external beam radiation therapy was associated with significantly worse median overall and disease-specific survival compared with no additional local-regional therapy: 31 and 45 months vs 51 and 98 months, respectively (P Conclusions The use of adjuvant external beam radiation therapy is associated with a significant decrease in overall and disease-specific survival for patients with T1-2N0M0 non-small cell lung cancer treated with sublobar resection. Although this finding may be related to covariables not reported in SEER, such as margin status, chemotherapy use, radiation dose, and portal, alternative radiation treatment strategies should be explored.

Purpose: The purpose of this study was to analyze the relationship between prostate, bladder, and rectum volumes on treatment planningCT day and prostate shifts in the X Y Z directions on treatment days. Methods: Prostate, seminal vesicles, bladder, and rectum were contoured on CTimages obtained in supine position. Intensity modulated radiation therapy plans was prepared. Contours were exported to BAT-ultrasound imaging system. Patients were positioned on the couch using skin marks. An ultrasound probe was used to obtain ultrasoundimages of prostate, bladder, and rectum, which were aligned with CTimages. Couch shifts in the X Y Z directions as recommended by BAT system were made and recorded. 4698 couch shifts for 42 patients were analyzed to study the correlations between interfraction prostate shifts vs bladder, rectum, and prostate volumes on planning CT. Results: Mean and range of volumes (cc): Bladder: 179 (42–582), rectum: 108 (28–223), and prostate: 55 (21–154). Mean systematic prostate shifts were (cm, ±SD) right and left lateral: − 0.047 ± 0.16 (−0.361–0.251), anterior and posterior: 0.14 ± 0.3 (−0.466–0.669), and superior and inferior: 0.19 ± 0.26 (−0.342–0.633). Bladder volume was not correlated with lateral, anterior/posterior, and superior/inferior prostate shifts ( P > 0.2 ) . Rectal volume was correlated with anterior/posterior ( P 0.001 ) but not with lateral and superior/inferior prostate shifts ( P > 0.2 ) . The smaller the rectal volume or cross sectional area, the larger was the prostate shift anteriorly and vice versa ( P 0.001 ) . Prostate volume was correlated with superior/inferior ( P 0.05 ) but not with lateral and anterior/posterior prostate shifts ( P > 0.2 ) . The smaller the prostate volume, the larger was prostate shift superiorly and vice versa ( P 0.05 ) . Conclusions: Prostate and rectal volumes, but not bladder volumes, on treatment planningCT influenced prostate position on treatment fractions. Daily image-guided adoptive radiotherapy would be required for patients with distended or empty rectum on planning CT to reduce rectal toxicity in the case of empty rectum and to minimize geometric miss of prostate.

In breast cancer (BC) patients the brachial plexus syndrome (BPS) has been reported to be due to loco-regional metastases or radiation plexopathy. Associated arm edema is considered more suggestive of the latter. Radiation therapy is the only effective treatment for BPS reported. The charts of all BC patients who presented to our clinic from 1982 to 2006 with homolateral arm pain and neurological deficits, without humerus, cervical spine, or brain metastases, were reviewed. There were 28 patients fulfilling these criteria for BPS. Supraclavicular, axillary or chest wall metastases developed synchronously with the BPS in 26 patients; in 21 they were recurrences, found 6–94 months (median 34 months) after primary BC treatment, while in 5 others they were progressing inoperable primary tumors and nodes. Arm edema first occurred at the same time as loco-regional metastases in 19 patients. Treatment for the BPS was administered to 22 patients; it was directed at their locoregional metastases. The BPS was initially treated with radiation (8 patients) or chemo- or endocrine therapy (14 patients); 19 (86%) had partial or complete remission of pain and neurologic deficits, with an 8-month median duration. The BPS in BC patients is due to loco-regional metastases and is often associated with arm edema. Chemoor endocrine therapy induced the remission of pain and deficits as frequently as radiation therapy.

Carcinoma of anus, Chemo-radiation therapy, 5-fluorouracil, 5FU, Mitomycin C, COncomitant infusion, Local control and survival, Clinical results, Hybrid spheroid assay.

The clonogenic hybrid spheroid assay has been used to determine the toxicity of 5-fluorouracil (5-FU), alone or in combination with indomethacin, in LoVo cells (a human colon adenocarcinoma line). The principal finding was that 5-FU toxicity, determined as loss of colony-forming ability, increased as a function of dose (concentration x duration of exposure). and that indomethacin causes a generalized alleviation of 5-FU toxicity, but only if given concurrently with 5-FU. The implications of these findings in the control of cancer cells by 5-FU are discussed.

We have measured survival after successive 2-Gy doses of X rays in HeLa cells and 1-Gy doses in cells of the nonimmortalized human fibroblast cell line AG15-22 under conditions where any effect of cell proliferation during multifraction X irradiation has been factored out. When HeLa cells in parallel series of (pseudo)hybrid spheroids (i.e. in agglomerates consisting of a mixture of supralethally irradiated HeLa feeder and viable HeLa cells) were exposed to n daily radiation doses and then trypsinized and exposed to the last dose, the surviving fraction at 2 Gy (SF2) declined exponentially from 0.55 +/- 0.01 to 0.31 +/- 0.01 after the fifth fraction. In monolayer HeLa cell cultures, the decline in SF2 was smaller but significant and was not influenced by the presence of feeder cells. Pure spheroids, composed entirely of viable HeLa cells, showed the same decline in SF2 as did monolayer cells. The cumulative-effect curve (i.e. the product of SF2 values) was linear-quadratic with the quadratic term increasing in the order monolayer, pure spheroids, pseudohybrid spheroids. SF2n and D0Eff (deduced from the initial SF2) severely underestimated cumulative radiosensitivity. This cumulative effect is clearly associated with the proximity of lethally irradiated cells and might be explained by differential population shifts in the course of the multifraction regimen. Similarly, AG15-22 cells irradiated with daily 1-Gy doses of X rays showed a larger increase in radiosensitivity when in hybrid spheroids than when in pure spheroids. However, for the AG15-22 cells, SF1 was twofold lower for the former than for the latter condition and remained constant for both conditions rather than decreasing with increasing fraction number. This large radiosensitizing effect remains unexplained.

The Hybrid Spheroid assay is based on packaging tumor cells into agglomerates of non-proliferating, but metabolically active, HeLa cells. These agglomerates provide an in vivo-like environment for entrapped test cells. Clonogenicity is determined by varying the number of test cells per hybrid spheroid so that some, but not all, spheroids give rise to macrocolonies. From the fraction of noncolony forming spheroids and the Poisson distribution, the average number of clonogens per spheroid can be calculated. The clonogenicity and radiation survival curves of cells derived from human tumors (of the maxilla, tongue, larynx, mouth floor, lung, breast, ovary, and colon) were so determined. Plating efficiency was increased in these normally poorly plating tumor cells, thus enabling survival measurements which are not practical using conventional methods. The Hybrid Spheroid assay has also been applied to determine the chemosensitivity of colon cancer cells.

Purpose: To study the influence of combinations of Linear Accelerators and treatment planning‐systems, anatomical site and PTV volumes on MUs, and the magnitude and direction of deviation of prostate and H&N IMRT plan QA dose from plan‐dose. Method and Materials:IMRT plans were generated using Pinnacle3 or Eclipse treatment planning‐systems for treatment with Elekta or Varian Linacs, respectively. There were 29 H&N plans for Varian, and 59 and 33 prostate plans for Varian and Elekta, respectively. Dose at a point in the MED‐TEC phantom was measured with MT‐ERI‐A12 ion chamber. QA results were calculated as percentage deviation between measured and calculated doses in the phantom. A deviation of ±5% was acceptable. The magnitude and direction of deviation of QA results vs. PTV volumes, treatment site, Linac and planning system combinations were studied. PTV volumes vs. MUs was also analyzed. Linear regression analysis was used to study the relationship between paired variables. Results: The direction and magnitude of QA result deviation was Linac dependent. For Elekta prostate cases, QA measured dose deviated to negative direction (−2.49±0.93, −0.5 to −5%). For Varian cases, QA measured dose for prostate (1.67±0.91, −0.1 to 4.9%) and H&N cases (3.58±1.80, 0.2–6.4%) deviated to positive side. These results suggest that the delivered dose could vary between Linacs and might result in under‐ or over‐dosing. Prostate QA result deviation was independent of PTV volumes (P>0.1), but MUs increased with increase in PTV volumes (P

Evidence is presented for the interaction of X irradiation, slightly toxic levels of chloroquine, and mild hyperthermia in the inactivation of colony-forming ability in asynchronous HeLa cells. A three-way interaction was observed which resulted in the potentiation of radiation-induced lethality. There was little evidence of toxicity in unirradiated cells incubated for 3 h with 0.1 mM chloroquine at either 37 or 41 degrees C. The radiopotentiation factor, which is similar to the dose modification factor, was determined from dose-response curves by relating the reciprocal of the slope (D0) of the reference survival curve to that of the survival curve of cells receiving the combined postirradiation treatment with chloroquine and mild hyperthermia. Radiopotentiation factors larger than 1.7 were obtained irrespective of whether the reference D0's were obtained from survival curves for cells irradiated at 37 degrees C without drug or from cells receiving postirradiation treatment with heat or drug only.

We studied the influence of trypsin-induced morphological changes on the radiosensitivity of cells plated at either low (4-600/cm2) or high (2 x 10(4)/cm2) density and grown overnight before treatments. Trypsin treatment induced contraction and rounding of spread cells. The radiosensitivity of cells trypsinized and plated either: (1) immediately before [(a) D0 = 1.7 Gy for cells at low-, and (b) 1.5 Gy at high-density] or (2) immediately after (D0 = 1.6 Gy, high-density cells) irradiation was higher than that of (3) cells at high density, irradiated and delayed plated [cells remained spread until the completion of potentially lethal damage repair (PLDR) and trypsinization, D0 = 2.2 Gy], and (4) cells at low density which were neither delayed plated nor trypsinized (i.e. remained spread) after irradiation (Do = 2.4 Gy). These data show that PLDR is reduced in trypsin-treated cells of both high (compare 1b and 2 with 3) and low (compare 1a with 4) density cultures; the latter comparison provides a direct measure of the trypsin effect. Since the comparison between conditions 1 and 2 vs. 3 and 4 is of round vs. spread cells, PLDR appears to be influenced by the cell's morphological state. Kinetic studies showed that when cells were incubated in growth medium to recover from trypsin-induced effects before irradiation, the radiation sensitivity of spread cells (plated in situ), but not of those remaining rounded (in suspension until plating and irradiation), decreased and became equal to that of delayed plated high-density cells. Neither irradiated cells treated with hypertonic saline, nor mitotic cells, showed the trypsin effect. From these results we suggest that: (1) trypsin-induced cell contraction affects the ability of cells to repair radiation damage, (2) spread cells are better able to repair PLD than rounded cells, (3) immediate plating survival of cells in high-density cultures may not represent their intrinsic radiosensitivity and (4) cell-to-cell contact is not necessary for log phase cells to repair PLD.

Chinese hamster V-79 cells were exposed in suspensions for 1–15 min to 1.1 MHz continuous wave (CW) ultrasound at axial intensifies from 0.25–30 W/cm2. Cell lysis was evidenced by a decrease in the number of intact cells, and loss of reproductive integrity was evidenced by a decrease in the plating efficiency of the remaining intact cells. The magnitude of these effects was a function of both intensity and exposure duration. Mitotically synchronized cells displayed a differential sensitivity depending upon cell cycle position. The M and S phases of the cell cycle were more resistant with respect to cell lysis and loss of reproductive integrity than were the G1 and G2 phases.

Exposure of Chinese hamster V-79 cells to 1.1-MHz continuous wave (CW) ultrasound at intensities of 10, 20, and $30\ {\rm W}/{\rm cm}^{2}$ resulted in cell lysis and the loss of reproductive integrity (i.e., a decrease in plating efficiency) in the remaining intact cells. Sonication in the presence of 8 mM cysteamine, a free-radical scavenger, did not alter the amount of cell lysis, but did result in a smaller decrease in plating efficiency at 20 and $30\ {\rm W}/{\rm cm}^{2}$ . Hence, while free radicals do not appear responsible for ultrasonically induced cell lysis, free radicals do appear to be at least partially responsible for loss of reproductive integrity in the remaining intact cells.